pokered/engine/gfx/oam_dma.asm
2024-01-03 10:59:04 -05:00

28 lines
450 B
NASM

WriteDMACodeToHRAM::
; Since no other memory is available during OAM DMA,
; DMARoutine is copied to HRAM and executed there.
ld c, LOW(hDMARoutine)
ld b, DMARoutine.End - DMARoutine
ld hl, DMARoutine
.copy
ld a, [hli]
ldh [c], a
inc c
dec b
jr nz, .copy
ret
DMARoutine:
LOAD "OAM DMA", HRAM
hDMARoutine::
; initiate DMA
ld a, HIGH(wShadowOAM)
ldh [rDMA], a
; wait for DMA to finish
ld a, $28
.wait
dec a
jr nz, .wait
ret
ENDL
.End: